It is simple to understand after this pic. I add fewtextfields in tableview I already set the keyboard style is number pad. Now the problems is 1.Do I need to create 12 textfields ???ex. UITextField *ip1,ip2,ip3,ip4....or just set different tag for textfield ? 2.How to check user enter wrong char not 3 valid numbers (even the keyboard is set number pad,but it might can paste words...) 3.How to check user did follow this setting rules ??? <1If IP1 is 0~223 , IP2 need to be set 0~255,IP3,IP4 both are 0~255 <2If IP1 is 172 ,IP2 is set 16~31.IP3,IP4 both are 0~255; If IP1 is 192 ,IP2 must be 168.IP3 IP4 are 0~255 <3Netmask set default 255.255.255.0 <4Router 0~223 ,0~255 ,0~255 ,0~255 This IP setting rules is my friends tech me this ...I not sure the rules is right or not?